Hi, i'm new here. Soooo, i just bought a symmar on ebay for a project of mine and i would like to ask something. How much do i have to move the lens to get it to focus from it's closest focus to infinity? Would it be possible to use a helicoid to do this?
Focusing at infinity will require ABOUT 135mm of distance between the film and the lens. How close you can focus depends on how much ADDITIONAL extension you can create between the lens and the film.
Ah, i see. Then if i wanted it to focus about a metre from me, roughly how much more do i need. Was thinking of using a helicoid.Originally Posted by xkaes
It depends on where "about a metre from me" starts. If you want 1 m film plane to subject distance, with a 135 mm lens that means a magnification of ~ 1:5 and you'll need ~ 27 mm extension from the infinity position. A little more wouldn't hurt.
Thanks. How did you get the 1:5? Any formula for it or something?
But the helicoid that was made for this lens will not get you much closer then about 6’.
Was thinking of getting one of those chinesr made ones from ebay and modifying it. Didn't know there was one made for this lens, i'll have look for it. Thanks
Yes. Please see post #2 in this discussion.
If you want to learn more about close up work and especially the magic formulas, buy a copy of Lester Lefkowitz' book The Manual of Closeup Photography. Quite inexpensive used from booksellers who hawk their wares on venues such as abebooks.com, alibris.com, amazon.com, bn.com, ...
Will do, thanks.
Sorry, I failed to put the link in. This discussion: http://www.largeformatphotography.in...n-bellows-draw
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